There are two separate issues here. Repairability and upgradability. Both are problems but repairability is even worse these days.

For me except the keyboard, the battery and the screen should be easily replaced, preferably by the user.

Thinkpads used to have both easily done but not any longer. Batteries are guaranteed to go bad after 3-4 years. Screens can easily be damaged.

Recent laptops have both glued which is unacceptable (e.g. Macbook) and I refuse to buy them.

That's why I switched from Carbon X-1 to T14.
Pretty much the same features -- except with Ethernet port and easily replaceable keyboard.
Yes, the Carbon is a little sleeker -- but the Gen 6 model has a keyboard held in place with 70+ screws if you can get to it at all.  Have to take everything out first.

The major reason is simple: planned obsolescence. The manufacturers sell new products more frequently to those buying notebooks at all. The manufacturers disregard those refusing to buy notebooks, building their own desktops and thereby avoiding the planned obsolescence. Politicians have mostly done nothing or too little for many decades but the EU is slowly and partially awaking.

Back in the day, my business laptop let me take out ram, hard drive, battery, wifi and etc without even needing a screw driver. The keyboard replacement was 2 screws and those screws were on springs so you don't lose them or deal with alignment issues. The laptop wasn't even that thick.

Those were the good days.

But yeah, part of the problem is no one holds these manufacturers accountable for repairability or includes it in their ratings. All we get is more throw away stuff.

NBC should call this out more often in the reviews. The only reason why manufacturers are so hostile against repair access is because media and consumers allow them to go Apple on us.